Chaves helped write the critically acclaimed stage drama Tracers. In the early 1980s, he began work as an actor taking on various soap opera roles until he gained a notable role in 1987 as Poncho in the science fiction film Predator. Soon afterward, his career received another boost with the role of Lt. Colonel Ironhorse in the television series War of the Worlds As well as having a character that allowed him to get in touch with both his Native Americanheritage and a military history, the series also brought him a large fanbase. Chaves once calculated that the volume of fan mail he received outnumbered the rest of the cast members by a four or five to one ratio.
However, his career hit a bump when War of the Worlds was given new creative management for its second season. The new executives did not think that the Ironhorse character worked with the format they wanted for the show, so his character and that of Norton Drake were killed off.
In the late 1990s, Chaves became the subject of a stalker. To protect himself, his family and friends, he followed the advice of police by refraining from attending conventions and closing his official website.
Chaves has made few public appearances over the years since being stalked. He appeared at the Las Vegas Comic-Con in October 2003; in late 2006 he was photographed with Frances Fisher at the Flags of our Fathers premiere; he was a guest at the Chicagoland Entertainment Collectors Expo in October 2007; he appeared at the Gallifrey One convention in February 2007, and is scheduled to attend again in February 2008. His most recent acting appearance is in the soon-to-be-released film Lost Warrior: Left Behind and "Dark House".
In June 2009, he was present in Star Guest of "Collectormania" at the Stadium Way West, Milton Keynes, UK.